This invention relates generally to signs which are mounted on the roof of a vehicle such as an automobile or van, and, more particularly, to a sign such as a school bus sign which can be mounted on the roof of a vehicle and then unfolded into a vertical position when it is to be in use or folded into a horizontal position when it is not to be in use by a latching mechanism connected to each end of the sign yet capable of being operated from one end thereof.
With the constantly increased demand for transportation, especially in the area of conveying children to and from schools or day care centers, there has been a dramatic increase in the need for vehicles capable of effecting this transportation. Unfortunately, providing specifically constructed marked buses and vans which can be used solely for the transportation of passengers becomes an expensive undertaking. In many instances the expense per passenger per mile is far too great to justify the cost of maintaining such vehicles. It has therefore become common practice to utilize passenger vehicles such as station wagons and vans as acceptable and efficient alternate forms of transportation, especially when specifically manufactured buses and vans are unavailable or not practical to use.
In the case where passenger vehicles are utilized as school buses, for example, it is a state and federal requirement that such vehicles be appropriately marked as such and also contain appropriate warning lights. In order to meet these requirements auxiliary signs have been manufactured which contain a suitable space thereon for the appropriate markings (such as a SCHOOL BUS designation) as well as having mounted thereon warning lights. These signs are generally affixed to the roof of the vehicle. In some instances the signs are permanently secured to the roof of the vehicle by bolts or the like; however, in the preferred arrangement, the sign is removably mounted on the roof such as means of gutter clamps in a similar manner to the securing of ski racks.
Quite often, these signs are mounted on the roof by a mechanism which allows the sign to be pivoted or folded so that it can be positioned in either a vertical (upright) position or a horizontal position. When the vehicle is being used for the purpose indicated by the sign, the sign is placed in the vertical position. On the other hand, when the vehicle is not being used for the purpose indicated by the sign or when going through car washes and the like the sign is placed in a horizontal position.
One of the problems encounted with foldable signs currently available is a result of the latching system used to lock the sign in the vertical and horizontal position. To date, these latching systems have consisted of a pair of latching mechanisms (such as barrel bolts or spring clips) attached at opposite ends of the sign in order to fixedly support the sign in the desired position. To operate such prior art latching systems, the driver of the vehicle must affix or release each one of the two latching mechanisms in order to effect the appropriate folding or opening action associated with the sign. This involves walking around to the passenger side of the vehicle to release the latch mechanism of that side thereof since the latch mechanism on the passenger side cannot be reached by the driver while standing on the driver's side. In order to avoid the necessity of the walking around to the passenger side of the vehicle to activate the latch mechanism on that side thereof, there has been a tendency for the driver/operator to secure the sign in the desired position by activating, i.e. using only the latch mechanism on the driver side of the vehicle and not using the latch mechanism on the passenger side. In some instances the use of the latching mechanism on one side of the sign as offered to the latching mechanism on both sides of the sign may prove effective; however, in most situations using only one latching mechanism creates a condition which not only places tremendous strain on the sign, but also may lead to a dangerous condition if the single latching mechanism becomes insufficient to hold the sign securely in place.
A typical problem arises when the vehicle is driven at highway speeds and the resultant force created by the flowing air or wind causes the sign to bend or strain. Under that condition the single latching mechanism acts as a pivot point for the sign. Since the signs are generally made of a light weight material such as aluminum it is readily apparent that in a short time the sign will become practically useless. In fact, there have been situations where the sign has been completely sheared off the roof of the vehicle as a result of only latching the sign at one end thereof. Furthermore, prior foldable signs fail to provide any locking in the retracted position.
It is therefore abundantly clear that a great need exists for a foldable sign which is capable of being easily moved and secured in either an upright position or a horizontal position. This movement of the sign between the two positions would require only a minimum of effort on the part of the operator of the vehicle, yet once positioned in either the upright position or lowered position, the sign must remain in the desired position even when the vehicle is subjected to adverse environmental conditions, such as high winds.